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    <title>Document</title>
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    <script>
        //1.形参的初始值  具有默认值的参数，一般位置要靠后（潜规则）
        function add(a, b, c=10){
            return a + b + c
        }
        let result = add(1, 2)
        console.log(result); //13

        //2. 与解构赋值结合
        function connect({host="127.0.0.1", username, password, port}){
            console.log(host);//如果传值 就用传的值  没有传值 就用默认值
            console.log(username);
            console.log(password);
            console.log(port);

        }
        connect({
            host: 'baidu.com',
            username: 'root',
            password: 'root',
            port: 3306
        })
    </script>
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